Flaky test ComponentWithConstrainedTypeParameters

[BrennanConroy]

https://dev.azure.com/dnceng/public/_build/results?buildId=1107818&view=ms.vss-test-web.build-test-results-tab&runId=33812670&resultId=100474&paneView=debug

System.InvalidOperationException : Aborting compilation to assembly because RazorCompiler returned nonempty diagnostics: x:\dir\subdir\Test\TestComponent.cshtml(2,19): Error RZ1017: Unexpected literal following the 'typeparam' directive. Expected 'line break'.\nx:\dir\subdir\Test\TestComponent.cshtml(3,19): Error RZ1017: Unexpected literal following the 'typeparam' directive. Expected 'line break'.
   at Microsoft.AspNetCore.Razor.Language.IntegrationTests.RazorIntegrationTestBase.CompileToAssembly(CompileToCSharpResult cSharpResult, Boolean throwOnFailure) in /_/src/Razor/test/Microsoft.AspNetCore.Razor.Test.Common/Language/IntegrationTests/RazorIntegrationTestBase.cs:line 289
   at Microsoft.AspNetCore.Razor.Language.IntegrationTests.RazorIntegrationTestBase.CompileToCSharp(String cshtmlRelativePath, String cshtmlContent, Boolean throwOnFailure, String fileKind, String cssScope) in /_/src/Razor/test/Microsoft.AspNetCore.Razor.Test.Common/Language/IntegrationTests/RazorIntegrationTestBase.cs:line 217
   at Microsoft.AspNetCore.Razor.Language.IntegrationTests.RazorIntegrationTestBase.CompileToCSharp(String cshtmlContent, Boolean throwOnFailure, String cssScope) in /_/src/Razor/test/Microsoft.AspNetCore.Razor.Test.Common/Language/IntegrationTests/RazorIntegrationTestBase.cs:line 173
   at Microsoft.AspNetCore.Razor.Language.IntegrationTests.ComponentCodeGenerationTestBase.ComponentWithConstrainedTypeParameters() in /_/src/Razor/Microsoft.AspNetCore.Razor.Language/test/IntegrationTests/ComponentCodeGenerationTestBase.cs:line 239

Test was added on 4/19, but first failures I can see start on 4/22.

Also, would appreciate it if people didn't just retry the failing leg without filing an issue at a minimum

[pranavkm]

Would this explain the build failures we are seeing? This is pretty close to the scenario we're seeing with the build flakiness.

FYI @javiercn / @captainsafia

[captainsafia]

I think there's some general spookiness that is happening as a result of the generic parameters change. The error above seems to indicate that some faulty code is being generated?

[javiercn]

I would not expect flakyness in this type of test.

That might point out a larger issue within the compiler. Did we update the razor SDK to something recent? (I did the change where its only enabled in 6.0, so I'm wondering if somehow its receiving the wrong razorlanguageversion)

Thanks for contacting us.
We're moving this issue to the Next sprint planning milestone for future evaluation / consideration. Because it's not immediately obvious that this is a bug in our framework, we would like to keep this around to collect more feedback, which can later help us determine the impact of it. We will re-evaluate this issue, during our next planning meeting(s).
If we later determine, that the issue has no community involvement, or it's very rare and low-impact issue, we will close it - so that the team can focus on more important and high impact issues.
To learn more about what to expect next and how this issue will be handled you can read more about our triage process here.

[captainsafia]

Just saw this happen locally while doing some work locally on the Razor compiler.

   System.InvalidOperationException : Aborting compilation to assembly because RazorCompiler returned nonempty diagnostics: x:\dir\subdir\Test\TestComponent.cshtml(2,19): Error RZ1017: Unexpected literal following the 'typeparam' directive. Expected 'line break'.
x:\dir\subdir\Test\TestComponent.cshtml(3,19): Error RZ1017: Unexpected literal following the 'typeparam' directive. Expected 'line break'.
  Stack Trace:
     at Microsoft.AspNetCore.Razor.Language.IntegrationTests.RazorIntegrationTestBase.CompileToAssembly(CompileToCSharpResult cSharpResult, Boolean throwOnFailure) in /Users/captainsafia/github.com/dotnet/aspnetcore/src/Razor/test/Microsoft.AspNetCore.Razor.Test.Common/Language/IntegrationTests/RazorIntegrationTestBase.cs:line 289
   at Microsoft.AspNetCore.Razor.Language.IntegrationTests.RazorIntegrationTestBase.CompileToCSharp(String cshtmlRelativePath, String cshtmlContent, Boolean throwOnFailure, String fileKind, String cssScope) in /Users/captainsafia/github.com/dotnet/aspnetcore/src/Razor/test/Microsoft.AspNetCore.Razor.Test.Common/Language/IntegrationTests/RazorIntegrationTestBase.cs:line 217
   at Microsoft.AspNetCore.Razor.Language.IntegrationTests.RazorIntegrationTestBase.CompileToCSharp(String cshtmlContent, Boolean throwOnFailure, String cssScope) in /Users/captainsafia/github.com/dotnet/aspnetcore/src/Razor/test/Microsoft.AspNetCore.Razor.Test.Common/Language/IntegrationTests/RazorIntegrationTestBase.cs:line 173
   at Microsoft.AspNetCore.Razor.Language.IntegrationTests.ComponentCodeGenerationTestBase.ComponentWithConstrainedTypeParameters() in /Users/captainsafia/github.com/dotnet/aspnetcore/src/Razor/Microsoft.AspNetCore.Razor.Language/test/IntegrationTests/ComponentCodeGenerationTestBase.cs:line 241

The exception is coming from here. The value of declaration.Code when the exception arises is:

// <auto-generated/>
#pragma warning disable 1591
#pragma warning disable 0414
#pragma warning disable 0649
#pragma warning disable 0169

namespace Test
{
    #line hidden
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Threading.Tasks;
#nullable restore
#line 1 "x:\dir\subdir\Test\TestComponent.cshtml"
using Microsoft.AspNetCore.Components;

#line default
#line hidden
#nullable disable
    public partial class TestComponent : Microsoft.AspNetCore.Components.ComponentBase
    {
        #pragma warning disable 1998
        protected override void BuildRenderTree(Microsoft.AspNetCore.Components.Rendering.RenderTreeBuilder __builder)
        {
        }
        #pragma warning restore 1998
#nullable restore
#line 12 "x:\dir\subdir\Test\TestComponent.cshtml"
       
    [Parameter] public TItem1 Item1 { get; set; }
    [Parameter] public List<TItem2> Items2 { get; set; }
    [Parameter] public RenderFragment<TItem2> ChildContent { get; set; }

#line default
#line hidden
#nullable disable
    }
}
#pragma warning restore 1591